If r and s are integers and rs+r is odd, which of the following must be even
A: r
B: s
C: r+s
D: rs-r
E: (E) r2+s
A: r
B: s
C: r+s
D: rs-r
E: (E) r2+s
举一反三
- If r and s are integers and rs+r is odd, which of the following must be even A: r B: s C: r+s D: rs-r E: (E) r2+s
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